As manufacturers increasingly seek to offer products with improved sustainability, the availability of intermediates produced from bio-renewable and/or recycled materials becomes more leveraging. However, there remains a need for these products to deliver equal or better performance than their traditional petroleum-based alternatives at a comparable or lower price point.
Bio-renewable content alone can be misleading as an indicator of “green” chemistry. For example, when a food source such as corn is needed to provide the bio-renewable content, there are clear trade-offs between feeding people and providing them with performance-based chemical products. Additionally, the chemical or biochemical transformations needed to convert proteins, carbohydrates, or other bio-friendly feeds to useful chemical intermediates and products can consume more natural resources and energy, and can release more greenhouse gases and pollutants into the environment than their petro-based alternatives in the effort to achieve “green” status.
The safe disposal or reuse of waste materials from various sources is an environmental and economic challenge. Such wastes had typically gone into landfills, but as landfill capacity is becoming ever scarcer and disposal costs are continuously increasing, cost effective and environmentally acceptable alternatives are needed to deal with these waste materials. Waste streams are produced by a great range of industries and sources, including, e.g., the plastics industry, the automobile industry, the paper industry, consumers, the agricultural industry, including both crop and animal production, as well as the production of animal products (e.g., the meat, dairy, egg, and wool industries). Because of these environmental and cost challenges, there is a need to find practical uses for recycled polymers and waste streams. In other words, there is the need to utilize recycled polymers and waste streams to produce new polymers and building blocks for these new polymers.
The domestic poultry and egg industries produce a large amount of waste products such as feathers and down feathers. Bird feathers such as chicken feathers, chicken down, duck feathers, duck down, goose feathers, goose down, turkey feathers, and turkey down, are an abundant and renewal source of keratin. It is known that avian feathers can be formed into thermoplastic compositions by extrusion with glycol plasticizers and reducing agents such as sodium sulfite. Further, it is known that avian feathers can be partially hydrolyzed to form animal feedproducts or glycolyzed at high pressures with nontoxic, edible polyols in the presence of a feather degradation agent to form animal feed products. In this feed product technology, the polyols used are limiting relative to the final properties needed for an industrial polyol. See Bumla, N. A., et al., Process and Utilization of Feathers, Poultry Technology, Jul. 28, 2012; V. Saucedo-Rivalcoba, et al., (Chicken feathers keratin)/polyurethane membranes, Applied Physics A (2011) 104: 219-228; A. Ullah, et al., Bioplastics from Feather Quill, Biomacromolecules 2011, 12 3826-3832; U.S. Pat. No. 4,908,220, to Shih et al., issued Mar. 13, 1990; US Patent Application Publication No. US 2014/0060383 A1, to Wu et al., published Mar. 6, 2014; and PCT Patent Application Publication No. WO 2014/023684 A1, to Nestec S. A., published Feb. 13, 2014; which are all incorporated by reference herein in their entirety. There is a need to develop methods for utilizing this source of keratin for making industrial polyol intermediates that allow for a broad variety of polymer performance attributes in the final polymer application.
Industrial polyols are commonly used intermediates for the manufacture of condensation and addition polymers. These condensation and addition polymers include polyurethane products such as flexible and rigid polymeric foams, polyisocyanurate foams, coatings, sealants, adhesives, and elastomers. Additional condensation and addition polymers include polyester polyol intermediates that can be sued to make the above mentioned polyurethane and polyisocyanurate products. These industrial polyols depend on chemical attributes such as hydroxyl functionality, branching, linearity, hydrophobe content, aromatic content, aliphatic content, polyether content, hydrogen bonding, crystallinity, glass transition, melting point, and various other chemical features to provide the full range of performance benefits to the final polymer into which they are incorporated. The use of only edible glycols or polyols for the digestion of the keratin is a severe limitation to the range of properties and costs available to non-edible glycols, and additionally creates economic competition between food sources and performance industrial chemicals at a time when the world needs more affordable and available food sources.
It is apparent from the above there is an ongoing need for sustainable sources of polymeric materials which a help to reduce waste streams and provide further options for the use of under-utilized raw materials while at the same time avoiding the competition for raw materials that can be used both as food sources and performance industrial chemicals.